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dyes

...and, on cooling, revert to the original tightly packed structure. Dyeing at higher temperatures (120–130 °C [248–266 °F]) under pressure avoids the need for carriers. With the
Thermosol process, a pad-dry heat technique developed by the DuPont Company, temperatures of 180–220 °C (356–428 °F) are employed with contact times on the order of a minute.